la brie r



March 5, 1940.

L. E. LA BRIE BRAKE 5 Sheets-Sheet 1 Original Filed April 23, 1951 [NVEN TOR. E L4 3P/c unse@ A TTORNE Y.

March 5, 1940. E. I A BRIE" BRAKE Original Filed April 23, 1951 5 Sheets-SheetI 2 a M y 1. w

Y l z2 INVENTOR. Unsfx? E. L4 BQ/E A TTORNE Y.

March 5, 1940. E, LA am.; Re. 21,3804

BRAKE Original Filed April 23. 1931 5 Sheets-Sheet 3 IN1/mfom 0065/? E. .4 .5R/c

A TTORNE Y.

March 5, 1940. L. E. A BRIE BRAKE Original Filed April 23, 1931 5 Sheets-Sheet 4 .INVENTOR. ansa/P t'. 4 15P/- ATTORNEY.

Ansiusdluur-s,19in l l Re. 21,380'

naar Y a Luggrnnnriepeunt'msmmxnorm f dix Brake Company, SoutirBcnil,y Ind., a corporation o! Illinois No. 2,064,611, usted December 15, 193s, Serial No..53z,265, April z3, 1931. Application l for reissue August 14, 1937, Serial No. 159,116

. esclama. I(cl. isa-19s) j This invention relates te brakesl and is illusembodiments shown in the accompanying drawtrated as embodied in a novel type of shiitableings, in which: anchorage automobile brake. l'igure 1 is a vertical section through a com- UNITED STATES .PATENT oFFlc-E- One feature of the invention relates to arbination mechanical-'hydraulic brake of the type 5 ranging for fluid-pressure .application a brake described above, just inside the head of the of the type having a pair of floating or indibrake drum, showing the brake shoes in side s vidually-'shiftable shoes, i. e., arranged to shift elevation; g

individuallyfrom one anchor to another so that Figure 2 is a partial section on the line 2-2 both shoes have self-energizing characteristics ofl'igure'L showing the mechanical or emergency 10, in both directions of drum rotation. Preferably operating means; l.

there are twov fluid-pressure voperators adjacent Figure 3 is a section, at right angles to Figure the opposite ends of the shoes, and these opera'- 2, on the line l-J of Figure 1, and also showing tors in the forms illustrated in themselves emsthe mechanical operating means; t body a number of important features of novelty. i Figure 4 is a section corresponding tolligure 1, 15 One important object relates to simplifyingl but showing va -diiferent brake, and with. the 15 theswear adjustment of a brake of this type, by mechanical operating means omitted: utilizing adjustable (i. e., expansible) anchors Figures 5 and 6 are sections through the brake instead of attempting to adjust the shoes, This of Figure 4, respectively on the lines l-l and is especially desirable in combination with a 0-3 0f Figure 4; gg fluid-pressure system of the well-known type, Figure 7 is a Section corieSpOnding i0 Figures 1 .o

no w practically universal commercially, in which and 4, but showing a different brake: a light pressure ismaintained in the system Figures 8 and 9 are sections through the-brake even when the brakes are released, as the oper- 0f Figure '7, respectively 0n the lilies 3-9 and ating pistons under the influence of this light 9 0 of Figure '1; g5 pressure follow the shoes out automatically as the Figure lii is a section corresponding i0 Figures 5 anchors are adjusted. As this type of system 1, 4 Bild '7, but ShOWing u fourth bra-ke: IIIWBYS includes, in the'master cylinder' at the Figures 11 and 12 are sections through the i, pedal, means for automatically keeping the sys brake of' Figure' lil,l respectively on the lines tem full of llquid, the adjusted released positions II--II and iI-I2 of Figure 10; so of the pistons are automatically compensated for Figure 13 is a more or less diagrammatic* 30 in the master c under, and the .anchor adjustshowing 0f s complete braking system according ments are there ore the only adjustment; in the to my invention; and entire system, this not being true of any of the Figure 14 is a sectional view showing the master previously-known.arrangements of wear adjust# cylinder oi' Figure i3. at ments for brakes of this type. In the brake of Figures 1, 2 .and 3, there isa 35 An important'feature of the invention relates rotatable drum I Il, at the open side-of which tc eliminating shifting i the shoes un forward is a support such as a -novel backing plate I2. application, 'preferably by using a piston at the and Within which is lilinged the bl'fke ,friiiiiOn toe of each shoe whichis larger in diameter than means which in this case comprises a .Dir 0f 40 the piston at the heel, so that the return springs floating and individually-shiftable shoes I4 and 4o will hold the heelsI of the two shoes continuously i0. The brake is provided at opposite Sides with anchored in forward application, although pera pair of anchorages for the shoe ends, shown mitting the toes oi' the shoes to shift into enas a pair of anchor posts Il and 20 carried by 4'gagem'ent with the anchors on reverseapplica thebacking plate and seated in notches in the a tion. i s l ends of the shoes and provided with elongated t .Other features relate to a novel duplex me retaining washers engaging the Sidej 0f th# chanlcal applying device -capable of being used Yshoes to hold them laterally (see especially-F18'- as an emergency connection from theusual hand ure 3). Return springs 24 are tensioned be lever when the, above-described iiuid-pressure tween the shoes at their opposite ends.

50 brakes are for service, to a. simple and The brake'is applied by novel duid-pressure 60 l ,effective automaticadjustment for wear capable*v means, which in this embodiment includes a of embodiment in the wheel cylinders, and to pair of hydraulic wheel cylinders 26 secured to various novel land desirable particular constructhe backing plate adjacent each anchorage, and i tions and arrangements which will be apparent within each of which .is arranged a relatively from .the following description of the illustrative 'large diameter piston 2l acting ou the toe of Il -one ofthe shoes (l. e., on the part of the which leaves the anchorage during forward braking) and a. relatively smaller diameter piston 33 acting on the heel of the other shoe (i. e.; on the part of the shoe which remains anchored shoe on forward braking). The pistons may have suitable rubber packing cups 32, shown held by a light spring 34 compressed between them.

By this arrangement, since the springs 24 pull equally on the two shoes, and since the larger diameter pistons 28 thrust outwardly with more power than the smaller diameter pistons 30, with any given iluid prewire in the line and in the cylinders 26 between the pistons, the pistons 33 do not operate to shift the heels of the shoes away from their anchors at any time during forward braking, but merely move far enough to follow the shoes as shoe I4 pivots on anchor I8 and shoe I6 pivots on anchor 20. 'I'hus during forward braking, due to the diierential action of the pistons and the equal action of the return springs, the shoes remain continuously anchored instead of leaving the anchors and then coming back with a shock underload.

During reverse braking, the action is the same until the shoes engage the drum, whereupon the shoes shift to the opposite anchors under the innuence of drum friction, the liquid-nlled cylindersserving in a manner analogous to door checks to slow up the shifting and minimize shock.

, For emergency application by the usual hand lever, especially when the brakes are on the rear Wheels, the brake may have a pair of mechanical applying`A devices such as oating levers or cams 3B notched out to clear the anchors I3 and 20 and having thrust projections 38 extending at right angles therefrom between theends oi the shoes, the bodies of the levers being arranged betweenthe backing plate and the web o f shoe I 4.

Levers 38 are operated by means such as a tension element or cable 4I) connecting their up per ends and operated by a second cable 42 or the vlike secured approximately at Yits center. Cable 42 extends at right angles to the brake, through a tubular projection 44 integrally 'drawn in the backing plate and against the end o! which engages and reacts the end oi a' iiexible Bowden-type conduit 43 housing that part of cable 42 which is outside the backing plate.

. In eil'ect the drum III and backing plate I2 form a closed brake chamber housing the movable parts, and conduit 43 forms a flexible extension of the brake chamber housing the operating cable 42 or its equivalent. The 4other end oi` conduit 43 is in most cases secured to the chassis frame, and the cable 42 issues therefrom and is secured to any desired type of connection from the hand lever.

The shoes I4 and I3 may be held yieldingly in place by any suitable spring steady rests 43. The pistons are shown acting on the shoes through piston rods 50 rounded at their piston-engaging inner ends and slotted at their outer ends to embrace shoulders formed on the webs oi' the shoes.

In the arrangement of Figures 4, 5 and 6, shoes I|4 and IIB are operated by the above-described differential diameter pistons 23 and 33, against the resistance of the return springs 24, all as heretofore described. In this case, however, novel anchorages are provided which not only take the torque oi' the brake but which are also adjustable to compensate f or wear of the brake lining. In the form illustrated in these particular figures.

the anchors proper'are two threaded posts 32 having conical or wedge heads 34 engaged by the conical ends of anchor links 33 pivoted to the ends of the shoes.

lLinks 33 pass, with sui'iicient clearance to prmit them to shift slightly erosswise with a pivotal action on the anchor heads 54 during application and release of the brake, through sleeves 53 at opposite sides oi housings 33 secured to the backing plate and into which the anchor posts 32 are threaded as shown in Figure 5. The tubular centrai portion of each housing may be closed by a stamping 62. Thus turning the posts 32 operates the wedges 54 to force links 33 slightly apart to take. up for wear of the lining on the brake shoes.

'I'his is especially advantageous where the cylinders 26 are connected to a hydraulic system of the type,.now universally used commercially, in which the iiuid in the hydraulic lines is maintained under a light pressure or four or ve pounds per square inch, insuicient to overcome springs 24 but sumcient to insure that no air will be sucked into the line. A hydraulic brake system so arranged is disclosed in Figures 13 and 14 wherein is shownvk a master cylinder 42| having pistons 423 and 423adapted to be actuated by a pedal 421 to force nuid under brake actuating pressure through conduit 423 to the cylinders 23 to apply the brakes. The pedal is convnected to the pistons by pedal link 43|. The iiuid is maintained under predetermined pressure by a pressure maintenance piston 433 positioned in an auxiliary reservoir 433. Upon-the piston 433 a spring 431 bears and with said piston there is associated a spring pressed relief valve 433. 'I'he liquid in the system is maintained under a pressurevequal to the spring 44I associated with the valve 433.

With this type of iiuid pressure operating means, as the anchorages are adjusted to up for wear, the pistons 23 and 33 are moved automatically outward by the line pressure, following the shoes to their new adjusted positions,

and the master cylinder operates automatically,

as described in my Prior application, to introduce additional fluid into the lines to compensate for the new piston positions. Thus the only adjustments in the entire brake system which must be made bythe driver are those at the two anchorages at each brake, and oi' course it is only necessary to adjust one of these two during one brake adjustment.

Figures 5 and 6 also show a conduit 33 connecting the two cylinders 23, and a conduit 33 leading to the hydraulic lines on the chassis, which conduits do not appear in Figures 1-3, although of course they are used. Figure 5 also. shows one o! the removable set screws 13 used in bleeding" the hydraulic lines.

Figure 10, 11 and 12 show shoes 2I4 and 2I3 arranged to anchor slidingly at their heel ends against the plane end surfaces of adjustment star wheels 12 formed on adjustable thrust inembers or plungers 14 threaded into internalLv threaded pistons 13 having shoulders 13 anchoring against the ends of cylinders" mounted Aon the backing plate and serving as parts oi' the brake anchorage as well as oi' the applying means.

, pear-shaped openings 34 in the shoe webs. These ends of the shoes 'are acted on in applying the 1| cient power without such self-adjustment andthe shoes pivot on anchor posts 82. In this con- .made at the anchorages byturningthe twostar wheels 12, the backing plate having openings ,opposite the star wheels to facilitate the adjustment, the openings having suitable removable covers 92. Pawls 94 of spring steel mounted on the cylinders yieldingly engage the star wheels and hold them in adjusted positions.

Instead of using pistons of different sizes, and

u illustrate n'ieans partly equivalent to the differential-piston construction in brakes of the type covered by-this application, I show in Figure 10 relatively strong return springs 98 tensioned be- .tween the heel ends of the shoes and stationary parts such as the cylinders 80 or the backing plate i2, and weaker return springs 98 tensioned between the toe ends of the shoes and the cylinders or backing plate.

Thus in applying the brake, during forward braking the springs 98 hold the heel ends of the shoes .continuously anchored through l engagement of shoulders 'I2 with the vstationary cylinders, while during reverse braking the shoes open out with the heel ends anchored until the drum frictionshiftsthemtocausethetoeendsto anchor on the separate posts l2. braking there is a radially-sliding anchorage permitting the shoes to adjust` themselves to the drinn, while during reverse braking there is suilistructlon, as in Figures 4 8, the light line pressures in the hydraulic lines when the brake is. released hold the pistons against the shoe ends but cannot overcome springs 98 and ll.

Vdifferential as previously described,

agaist the equal tensions of the return springs 2l. I

The novel wheel cylinder device I2C contains coaxial cylinders for the two pistons Ill and nil, which cylinders are however separated by a solid w'all ill-and provided with se ate inlets lll.. The inlets i are controlledby cone valves lll s, having stems loosely but guidingly Sliding in passages in plugs M threaded into the side of the wheel cylinder device and seated against valve springs I which are light enough'to be easily overcome by springs I. 'Ihe passages containingthe valves are in open communication with each other through openings 842, and are also in open communication with conduit lll. ,The upper'walve 3l. is shown in brake applied position in Figure 8, and the lower one in bxake released position.

In operation, brake applying pressure on the Vunenmti'sime valves totelettmmgure s, and' this forces the liquid ahead of the valves into the cylinders below the pistons.- the pistons 328 moving first because of their greater area. AThis causes' the brake to be applied in the normal case, the shoes anchoring through engagement oi pistons III with the-wall I Ill. A

If, however, the brake has worn so that it is notfullyapplied whenthe valves Ill reachtheir clearance withrespect to the drum. As explained tional liquid behind pistons In if it takes place during forward braking, and behind pistons 339 Dining forward left-hand positions, additionalliquid can flow past the valves. around their loosely-fitting stems, into the cylinders to cause full application of the brake. When the brake is now again released, valves 8l.A move to the right for a pre- 5 determined distance until they seat, whereupon the additional liquid so introduced'is trapped in, the cylinders and holds the shoes in automatically adjusted positions with predetermined lo above. the master cylinder at thepedal automatically forces more liquid into the system to replace that trapped in the wheel cylinders. The above-described adjustment introduces the addiu if it takes place during reverse braking.

While several illustrative embodiments have been described in detail, it is not my intention'to limit thel scope of the invention to those particular embodiments, or otherwise than by the terms of the vappended claims. Some features of the present application are dominated by claims in Bendix Patent No.-2,074,717, issued March23, 1937, and 1n Dodge Patent No. 2,084,388, issued 25 June 22, 1937, and Sanford Patent` No. 2,048,472, issued July 21, 1936, and it is not my intention to claim herein any ofthe subject-matter of said Bendix and Dodge and Sanford patents. The inventions shown in Figures 1-3 inclusive are also disclosed and are claimed in my copending application 734,249, led July 9. 1934, and the' inventions shownvin Figures 13 and 14 are also shown and are claimed ln my copending application 499.921, filed December 4, 1930. L

'I'he inventions shown in Figures 7 to 9 inclusive are also shown and are claimed in my copending application Serial No. 24,388, tiled May 31, 1935.

I claim:

". 1. A. brake comprising, in combination with a rotatable drum. a pair of shoes engageable with the drum and eacharranged to anchor at one endwheh the drum is turning in one'direction and at its other end when the drum is turning in the otherdirection, return springs acting on the shoes, a pair of adjustable anchorages one' positioned between each pair of adjacent ends of ,said shoes, and duid-pressure means for forcing the shoes against the drum to apply the brake and which duid-pressure means in brakereleased position is under a positive pressure less f than the force of said springs to cause the ilidpressuremeans to expand automatically to compensate fo r adjustment of the anchorage means but without overcoming the return springs.

2. A brake comprising, in combinationl with arotatable drum, a pair of shoes engageable with the drum and each arranged to have one part anchor when the drum is turning in one direc- 'tion and to have another part anchor when the drum is turning in the other direction, return springs acting on the shoes, a pairof adjustable f/ .brake lcomprising a pair of shoes, an

' anchorage for each adjacent pair of shoe ends,

each ofzwhich anchorages is disconnectedly posifor wear of the shoes, return springs holding the shoes against their anchorages, a huid-pressure 4applying device for each Vadjacent pair of shoe tioned between its adjacent pair of shoe ends to receive anchoring thrust therefrom and each of which anchorages is adjustable to* compensate ends, and means for supplying fluid to said iluid pressure applying device in brake released position under a greater pressure than that of the hydrostatic head acting in brake applying direction but lessthan the brake releasing pressure of said springs.

4. A brake comprising a pair of shoes, an anchorage for each adjacent pair of shoe ends, each of which anchorages is disconnectedly positioned between its adjacent pair of shoe ends to receive anchoring thrust therefrom, return springs holding the shoes against their anchorages, and means comprising a duid under positive pressure greater than that of the hydrostatic head but less than the brake releasing pressure of the springs. and uid pressure applying devices maintained by said iiuid under pressure in contact with the shoe ends while the shoes are in brake released position.4

5. A brake comprising a pair of shoes each individually shiftable to anchor on one end in one direction of rotatation of the drum and on the other end in the other direction of rotation of the drum, a pair of cylinders one adjacent each pair ofshoe ends, and a pair of pistons in each cylinder and one ot which is of greater diameter than the other and which act respectively on said shoes. 6. A brake comprising a pair of shoes, a pair of cylinders one adjacent each pair of shoe ends, a pair of pistons in each cylinder and one of which is of greater diameter than the other and which 'act respectively on said shoes, and a pair of anchorages one adjacent eachpair of shoe ends.

7. A brake comprising a pair of adjustable wedge means at opposite sides of the brake, and a pair of individually shiftable shoes having parts at their opposite ends engaging said means both for positioning said shoes when the brakes are released and for anchoring the shoes when the brakes are applied, togetherv with a pair of iluid-pressure applying devices acting on said shoes, one adjacent each anchor, each of said :uid pressure applying devices including a' pair of piston means held in contact with the shoes both when the brake is being applied and when it is released.

` 8. A brake comprising a pair of adjustable wedge anchors at opposite sides oi' the brake, and a pair oi.' shoes having parts at their opposite ends engaging said anchors, together with a pair of huid-pressure applying devices acting on said shoes, one adjacent each anchor, each of said applying devices comprising a pair of oppositely acting pistons or the like of different diameters.

9. A brake having two huid-pressure applying wievices, each comprising a pair of oppositely- Q acting pistons oi' the like of different diameters.

10. A brake comprising a pair of oating shoes,

a pair of anchors arranged between the opposite a pair o! anchors arranged between the opposite ends of the shoes, return springs acting on the shoes, duid-pressure applying means also.

acting on the shoes, means comprising said springs and fluid pressure means .for holding one end of each shoe continuously anchored #during forward application and for permitting shifting of the shoes to the opposite-anchors during reverse application.

12. A hydraulic brake system comprising a pair ofshiftable shoes, iiuid actuators for the opposite ends of the shoes, means for supplying the actuators with uid under light pressure even when the brake is released and for supplying them with uid under increased pressure to apply the brakes, and anchorages for the opposite shoe ends, at least one of which is adjustable to compensate for wear of the shoeswhereby the iight pressure causes the actuators to follow up the shoes when the anchorage is adjusted to compensate for said wear,

13. A brake comprising a pair of separated shoes each engageable with, the drum, each arranged to anchor at one end when the drum is turning in one direction and at the other end when the drum is turning in the other direction, and each having each end positioned adjacent to but separated from one of theends of the other, a pair of anchors one positioned between each pair of adjacentshoe ends and with which said ends contact, said anchors being extensible to take up shoe wear and'both contacting with both of said shoes independently so that either may be extended to take up shoe wear of both of said shoes and so that the entire brake may be adjusted by the extension of either anchor, and applying devices acting on said shoes, one -adjacent each anchor.

14. A brake comprising a pair of separated vshoeseach having each end positioned adjacent to but separated from one of the ends of the other, a pair oi' anchors one positioned between each pair o! adjacent shoe ends and with which said ends contact, said anchors being extensible to take up shoe wear, and iluid pressure applying devices acting on said shoes, one adjacent each anchor and each o1' said applying devices comprising a pair of oppositely acting pistons or the like of ditl'erent diameters'.

15. A brake' comprising a pair of shiftable anchorage separated ,shoes each anchoring on one` of its ends when applied while the drumis turning in one direction and anchoring on its oppoin the opposite direction, means comprising a 'pair of anchorages one between each pair of adjacent ends ot said shoes for both takingthe torque of said shoes during braking and for positioning said shoes in their released position, means for adjusting each of said anchorages Aby a lsingle operation so that both the return posi- `site end when applied while the drum is turning tion and the anchoring position is adjusted and so that the entire brake may be adjusted by either of said anchorages, and applying devices acting on said shoes, one adjacent each anchor.

16. A brake comprising a pair of individually shiftable shoes, a pair of anchors interposed betweenL the ends of said shoes, springs for maintaining said shoes normally against the anchors, `apair of double diameter cylinders interposed .between the ends of said shoes, and va pair of pistons in each cylinder one of which is .of greater diameter than the other and both of which exert force against said shoes.

17. A brake comprising a pair of shoes, a pair oi anchors interposed between the ends of said shoes, springs for maintaining said shoes normally against the anchors, a pair of double diameter cylinders interposed Vbetween the ends of Vsaid shoes, and a pair of pistons in each cylinder one ot which is oi' greater diameter than the other and both of which exert force against said shoes whereby said shoes remain with their forward ends against the anchor except in rearward braking.

18. A brake comprising a drum, a backing plate, a pair oi' brake shoes, a pair o! hydraulic cylinders mounted on said backing plate, each adapted to actuate each ofv said shoes, and resilient means more effective at one end of said shoes than at the other for holding said shoes out ol'contact with the drum.

19. A brake comprising a drum, a support, a pair of individually shiftable brake shoes in said drum and each arranged to anchor at either end according to the direction of drum rotation,` two hydraulic-cylmders at opposite sides 'of the brake each containing two pistons acting respectively on the toe of one shoe and the heel of the other mits braking torque to the cylinder.

20. A brake comprising a drum, a backing plate, a pair oi' individually shii'table brake shoes in said drum each shoe being formed with a. pear shaped opening, a pair of anchor pins secured to said backing plate and extending respectively through said openings, means for moving said shoes into contact with said drum, and spring means for returning 'said shoes to released position so arranged qthat during all brake applications a portion ofthe rim offeach oi' said openings in contact with its associated anchor is retained 21.Abrakeccmprisingadrum,abacking Plate, pair of individually shiftable brakeshoes in said drum each shoe being formed adjacent oneend withapearshap'ed opening, apair ofanchor pins secured to said backing plate and extending respectively through said openings, means for anchoring the opposite ends of said shoes, means for moving said shoes into contact with said drum, and spring means for returning said shoes to released position so arranged' that during forward braking the forward end of each shoe is maintained continuously vin anchoring contact with its anchor.

22. In mechanism of the class described, the combination of a drum, a support, a brake shoe arranged to engage with said drum, a fluid motor at each end of said shoe, each said motor acting on said shoe and adapted to move saidshoe into engagement with said drum, an anchor for said shoe located adjacent to one of said motors, and a second anchor for said shoe comprising the end of the Vother motor. l

23. A hydraulic brake comprising a drum, a relatively stationary support, a pair oi'- hydraulic motors mounted on said support, a pair of brake shoes. 'each shoe being acted on by each motor, and resilient means for holding said shoes out of contact with the drum. said means acting more strongly on one end of said shoes than the other.

V 24. A hydraulic brake comprising a rotatable drum. a support, a pair of hydraulic cylinders mounted on said support, a pair of 4brake shoes, each shoe being actuated by each cylinder, a pair oi anchors for each shoe, a pair oi spring means for retracting said shoes, a portion of said spring means exerting a greater force on one shoe thfn on the other whereby one end of each shoe is pulled from the drum more strongly than the other end.

25. A' hydraulic brake system comprising a pair of shiitable shoes, iluld actuators for the opposite ends of the shoes. means for supplying the actuators with fluid under light pressure even when the brake is released and for supplying them with uid under increased pressure to apply the brakes, and anchorages for the opposite shoe ends, atleast one of which is adjustable to compensatefior wear oi' the shoe associated with said anchorage, whereby the light pressure causes the actuator associated with said last mentioned shoe to follow up said shoe when the anchorage is adjusted to compensate tor said wear.

LUDGER E. LA BRIE. 

